/*
 * ===========================================
 * Java Pdf Extraction Decoding Access Library
 * ===========================================
 *
 * Project Info:  http://www.idrsolutions.com
 * Help section for developers at http://www.idrsolutions.com/java-pdf-library-support/
 *
 * (C) Copyright 1997-2013, IDRsolutions and Contributors.
 *
 * 	This file is part of JPedal
 *
     This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA


 *
 * ---------------
 * PDFGenericFunction.java
 * ---------------
 */

package org.jpedal.function;

import java.io.Serializable;

/**
 * Contains code which are used by multiple Shading Classes
 */
public class PDFGenericFunction implements Serializable {

	private static final long serialVersionUID = 2585493215543078599L;
	/**
	 * values found in Function using names used in PDF reference
	 */
	protected float[] domain, encode, decode, range;

	public PDFGenericFunction(float[] domain, float[] range) {

		this.range = range;
		this.domain = domain;
	}

	/**
	 * Preform interpolation on the given values.
	 * 
	 * @param x
	 *            : current X value
	 * @param xmin
	 *            : lowest x value
	 * @param xmax
	 *            : highest x value
	 * @param ymin
	 *            : lowest y value
	 * @param ymax
	 *            : highest y value
	 * @return y value for the x value
	 */
	static float interpolate(float x, float xmin, float xmax, float ymin, float ymax) {
		return ((x - xmin) * (ymax - ymin) / (xmax - xmin)) + ymin;
	}

	/**
	 * Return the lowest of the input vairbles
	 * 
	 * @param a
	 *            : value 1 to check
	 * @param b
	 *            : value 2 to check
	 * @return The lowest of the input values
	 */
	static float min(float a, float b) {

		if (a > b) return b;
		else return a;
	}

	/**
	 * Return the highest of the input vairbles
	 * 
	 * @param a
	 *            : value 1 to check
	 * @param b
	 *            : value 2 to check
	 * @return The highest of the input values
	 */
	static float max(float a, float b) {

		if (a < b) return b;
		else return a;
	}
}
